jcs.org
Serenity Operating System
1/*
2 * Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
3 *
4 * SPDX-License-Identifier: BSD-2-Clause
5 */
6
7#include <LibCore/LocalServer.h>
8#include <LibCore/Notifier.h>
9#include <LibCore/SessionManagement.h>
10#include <LibCore/Socket.h>
11#include <LibCore/System.h>
12#include <LibCore/SystemServerTakeover.h>
13#include <fcntl.h>
14#include <stdio.h>
15#include <sys/socket.h>
16#include <sys/stat.h>
17#include <unistd.h>
18
19#ifndef SOCK_NONBLOCK
20# include <sys/ioctl.h>
21#endif
22
23namespace Core {
24
25LocalServer::LocalServer(Object* parent)
26 : Object(parent)
27{
28}
29
30LocalServer::~LocalServer()
31{
32 if (m_fd >= 0)
33 ::close(m_fd);
34}
35
36ErrorOr<void> LocalServer::take_over_from_system_server(DeprecatedString const& socket_path)
37{
38 if (m_listening)
39 return Error::from_string_literal("Core::LocalServer: Can't perform socket takeover when already listening");
40
41 auto const parsed_path = TRY(Core::SessionManagement::parse_path_with_sid(socket_path));
42 auto socket = TRY(take_over_socket_from_system_server(parsed_path));
43 m_fd = TRY(socket->release_fd());
44
45 m_listening = true;
46 setup_notifier();
47 return {};
48}
49
50void LocalServer::setup_notifier()
51{
52 m_notifier = Notifier::construct(m_fd, Notifier::Event::Read, this);
53 m_notifier->on_ready_to_read = [this] {
54 if (on_accept) {
55 auto maybe_client_socket = accept();
56 if (maybe_client_socket.is_error()) {
57 dbgln("LocalServer::on_ready_to_read: Error accepting a connection: {}", maybe_client_socket.error());
58 if (on_accept_error)
59 on_accept_error(maybe_client_socket.release_error());
60 return;
61 }
62
63 on_accept(maybe_client_socket.release_value());
64 }
65 };
66}
67
68bool LocalServer::listen(DeprecatedString const& address)
69{
70 if (m_listening)
71 return false;
72
73 int rc;
74
75#ifdef SOCK_NONBLOCK
76 m_fd = socket(AF_LOCAL, SOCK_STREAM | SOCK_NONBLOCK | SOCK_CLOEXEC, 0);
77#else
78 m_fd = socket(AF_LOCAL, SOCK_STREAM, 0);
79 int option = 1;
80 ioctl(m_fd, FIONBIO, &option);
81 fcntl(m_fd, F_SETFD, FD_CLOEXEC);
82#endif
83 VERIFY(m_fd >= 0);
84#ifndef AK_OS_MACOS
85 rc = fchmod(m_fd, 0600);
86 if (rc < 0) {
87 perror("fchmod");
88 VERIFY_NOT_REACHED();
89 }
90#endif
91
92 auto socket_address = SocketAddress::local(address);
93 auto un_optional = socket_address.to_sockaddr_un();
94 if (!un_optional.has_value()) {
95 perror("bind");
96 return false;
97 }
98 auto un = un_optional.value();
99 rc = ::bind(m_fd, (sockaddr const*)&un, sizeof(un));
100 if (rc < 0) {
101 perror("bind");
102 return false;
103 }
104
105 rc = ::listen(m_fd, 5);
106 if (rc < 0) {
107 perror("listen");
108 return false;
109 }
110
111 m_listening = true;
112 setup_notifier();
113 return true;
114}
115
116ErrorOr<NonnullOwnPtr<LocalSocket>> LocalServer::accept()
117{
118 VERIFY(m_listening);
119 sockaddr_un un;
120 socklen_t un_size = sizeof(un);
121#ifndef AK_OS_MACOS
122 int accepted_fd = ::accept4(m_fd, (sockaddr*)&un, &un_size, SOCK_NONBLOCK | SOCK_CLOEXEC);
123#else
124 int accepted_fd = ::accept(m_fd, (sockaddr*)&un, &un_size);
125#endif
126 if (accepted_fd < 0) {
127 return Error::from_syscall("accept"sv, -errno);
128 }
129
130#ifdef AK_OS_MACOS
131 int option = 1;
132 ioctl(m_fd, FIONBIO, &option);
133 (void)fcntl(accepted_fd, F_SETFD, FD_CLOEXEC);
134#endif
135
136 return LocalSocket::adopt_fd(accepted_fd, Socket::PreventSIGPIPE::Yes);
137}
138
139}